Billy Steele for Engadget:

In Boston this fall, you won’t need to keep up with your train ticket anymore — as long as you don’t leave your smartphone at home. The Massachusetts Bay Transportation Authority (MBTA) and Masabi have joined forces to bring a rail ticketing to handheld devices via iPhone, Android and BlackBerry apps.

This is a boon for the many Boston-area commuters who travel into the Hub via Commuter Rail stations that don’t have fare vending machines – less than half of the 140 stations in the MBTA’s Commuter Rail network have them, requiring those passengers to buy tickets from conductors on board.

Instead, you can buy tickets via credit or debit card. You can even link one of the MBTA’s “CharlieCards” to your phone.

Masabi, the company behind the e-ticketing system, says this will be its first deployment in the US. Masabi and the T are hoping to reduce the amount of cash-handling MBTA personnel have to do and other costs associated with ticketing and fare validation.